It had awful CA/purple fringing on high contrast subjects at f1.8 to f2.8 and the left side was soft

The only knocks against it that I could possibly think of are the purple fringing that it produces when being shot wide open, and a loss of contrast due to lens flare when shooting backlit subjects, such as someone with their back to the sun

but now when i look back at those wonderful pics, i can see bad color fringes

The weakness of this lens is noticeable purple fringing and the high price for a plastic body.

The fringing was so bad that on a 22mp 5dmii image processed in ACR CS5 with "defringe all edges" set to ON, I have 3/4 length shots of a bride where there is still a visible purple ring around most of her dress when viewed at an 8x10 size (not pixle peeping).... but 2 seconds later I took a similar shot from a different angle and got no fringe

The only problem I have with this lens is purple and green fringing on areas of high contrast.

Luckily almost every point and shoot digital camera suffers from much worse purple fringing so there are lots of actions in Photoshop to clear it up if you must remove it

i own a 35L, a 70-200mm f/2.8 IS, and a 16-35mm f/2.8L..and this lens is by far my most used lens.super sharp wide open, beautiful background blur, in my opinion the best bang for the buck other than maybe the 50mm f/1.8...which i've never owned.the only downside is the purple fringing, it produces some serious fringe wide open with extreme contrasty situations.

Even though this lens is awesome and is super sharp the only problem it has which can be fixed is the purple fringing when there is lots of contrast between dark and light

:Let me add to this regarding the "Purple Fringing" complaint which folks make about this lens particularly when compared to the 1.2 L. You can spend $1900 more and lose the fringing (most but not all) or spend $100 and buy Adobe Lightroom (which you need anyway) and slide the fader marked "Fringe" to the right about 5 notches

There is also some purple fringing in low light high contrast scenes (and likely some even in bright light).Lack of image stabilization IS hasn't bothered me much

I bought a 50mm f/1.8 lens which really got me interested in the faster f/stops to blur backgrounds and take pictures in lower light.

I also own the EF 50mm f/1.4, but of the two I prefer this lens.

Love the fast f-stop and sharp images it produces

The good:Fast aperture = great low light shootingInsanely sharp, almost as good as my 135 f/2LBad

This is a great lens for portraits and head shots and it is really sharp until you hit F/2.8 mark, then you can get fringing and chromatic aberration, and it is really soft at F/1/8It's not as sharp as the f/1.2 and the bokeh is not as buttery, but it's still pretty good for the money

fast AF+ f/1.8 and medium telephoto length allow you to isolate subjects+ Sharp enough wide open, very sharp stopped down to f/2.8-5.6+ VERY easy to travel with (compared to L counterparts)Cons:- AF not quite as accurate as L lenses (misses more than my 70-200 IS II or 50

The f/1.2 feels like an anvil is attached to the camera.

Sorry, 85 f/1.8, but back on the shelf you go.

Sturdily built but not heavy and bulky, wonderful bokeh, great f/stop control, clarity of image - my only problem with it, really, is that it isn't as sharp as I'd like, but that's all-too-easily fixed in Photoshop.

I needed a lens with an f/1.8 aperture to improve my portraiture work so that I could get tight focus on my subject while making the background into fuzzy focus.

Everybody and everything from your dog to the Queen of E looks silkier, more soulful and more loveable with this lens